Controlling means for the traveling offset web of multicolor-printing presses



July 13,1926. 1,592,055

. H- M. BARBER G OFFSET WEB 0F MULTICOLOR PRINTING iRlSSES Filed Oct. 31 1925 CONTROLLING MEANS FOR THE TRAVELIN INVENTOR ATTORNEYS UlT STATES HOWARD 1VI. BARBER, OF'WESTEELY, BEODE ISLAND, ASSIGNOR TO 0. B. CQTTRELL & SONS COMPANY, OF WESTER-LY, RHGDE ISLAND, A CORPQRATION OF DELAWARE.

CONTROLLING MEANS FOR THE TRAVELING OFFSET W'EB OF MULTICOLOR-PBINTING PRESSES.

Application filed October 31, 1925. Serial No. 85,977.

In multi-color web perfecting printing presses where a. traveling ofiset web is led around the impression cylinder of the sec- 0nd printing unit under the printed web, it has been difficult to obtain clean and sharp printing because of the tendency of the traveling offset web to travel at a different speed than the printed web as the printed web is fed around the impression cylinder by its contact with the printing surfaces of the plate cylinders;

In practical printing the surfaces of the plates are located below the bearer surfaces of their cylinders so that the surface speed of the bearers is slightly greater than the surface speed of the printing plates.

1 have discovered that if the traveling offset web be positively fed at the speed of the printed web, i. e., the surface speed of the plates, clean and sharp printing will be obtained as the tendency of the offset web to creep or crawl to change its relation to the printed web is entirely eliminated.

A practical embodiment of my invention is represented in the accompanying drawings, in which the plate and impression and cylinders of the second printing unit are denoted by 1, 2, 3, 4: and 5. The printed web is denoted by 6 and the traveling offset web by 7, which offset web is shown as leading from the supply roll 8 around the impression cylinder 5 to the takeup roll 9.

The means which I have shown for positively feeding the traveling offset web at the speed of the printed web is as follows:

A plurality of offset web feeding rolls, in the present instance three rolls 10,11 and 12 are positively driven through their gears 13. 14 and 15, and intermediate gear 16 from agear 17 of the impression cylinder 5 at a surface speed equal to the surface speed of the plates on the plate cylinder which is the same as the speed of the printed web. These offset web feeding rolls will entirely eliminate any tendency on the part of the offset web to change its relation to that of the printed web.

What 1 claim is 1. In a multi-color web perfecting printing press, a printing unit, traveling offset web, and means for positively feeding the offset web into the printing unit at the speed of the printed web.

2. In a multi-color web perfecting printing press, av printing unit, a traveling offset web, and means driven from the impression cylinder for positively feeding the offset web into the printing unit at the speed of the printed web.

3. In a multi-color web perfecting printing press, a printing unit, a traveling offset web, and offset web feeding rolls driven at the printing surface speed of the plate cylinders for positively feeding the offset web into the printing unit at the speed of the printed web.

4. In a inulti-color web perfecting printing press, a printing unit, a traveling offset web, and offset web feeding rolls driven from the impression cylinder at the printing surface speed of the plate cylinders for positively feeding the offset web into the printing unit at the speed of the printed web.

In testimony, that I claim the foregoing as my invention, I have signed my name this 28th day of October, 1925.

HOWARD M. BARBER. 

